Sealing profile

ABSTRACT

A sealing profile intended to seal a gap between the outer boundary of a motor vehicle door and its allocated opening of a motor vehicle construction comprises a tube-like construction that consists of at least two tubular profiles ( 4, 5 ) that are disposed one inside the other. The two tubular profiles are produced for example during co-extrusion and are formed in terms of construction and material with the proviso that the inner tubular profile ( 5 ) provides a resilient restoring force whereas the outer tubular profile ( 4 ) is chosen with regard to its surface properties, in particular the provision of a sealing function, which requires adaptation to dimensional inaccuracies and inequalities in the region of the boundary surfaces defining the sealing gap. An adhesive region ( 2 ) that is intended to connect to the one of the two boundaries is applied to the sealing profile. For example, the inner tubular profile can consist of silicone and the outer tubular profile can consist of sponge rubber or soft rubber. A product that fulfills all of the mechanical and thermal boundary conditions of the automotive industry and that can be used to the greatest possible flexible extent is provided.

The invention relates to a sealing profile in accordance with thepreamble of claim 1.

Sealing profiles are known in a variety of forms and are in the form ofeither a solid or tubular profile, wherein the cross-sectional formand/or the material are chosen with the proviso that good adaptabilityto irregularities as well as to dimensional inaccuracies of the gap tobe sealed and sufficient restoration capabilities are ensured.

The sealing profile remains under elastic stress until it has fulfilledits sealing function, when it is pressed against the boundaries that areopposite one another and define the gap to be sealed. This pressingforce in the region of the boundaries or sealing surfaces is to beuniform over time under the respective operating conditions so that thesealing profile will deform back to its original shape during thetransfer into an inactive unstressed state by converting the previouslystored elastic energy.

Further essential properties for a sealing profile relate to surfaceproperties, in particular suitability for connection to other materialswhich is important for example in motor vehicle sealing profiles.Finally, the sealing profile has to be efficiently producible on thebasis of the chosen material and must retain its properties, that areessential for fulfilling the sealing function, almost unaltered in atemperature range of at least −40° C. to approximately +110° C.

The above requirements are only partly achieved by the currently knownsealing profiles, in particular for tubular profiles.

A comparable tube-like sealing profile that is intended to be used inmotor vehicle doors is known from EP 0 836 962 A1 and consists of aninner profile that surrounds a hollow space, consists of an open-cellfoamed thermoplastic material having a low density and is surrounded onthe exterior by a of a [sic] closed-cell foamed thermoplastic profilehaving a higher density. A lateral portion of the outer profile is usedfor attachment to structural parts e.g. of a motor vehicle door. Whilstthe outer profile is used to provide sealing properties as well as apleasing visual appearance, the purpose of the inner profile is toprovide resilient properties as well as a sufficient creep resistance.The outer profile having the character of a coating has a thicknessbetween 0.5 mm and 1.0 mm, wherein this thickness is chosen in order topermit the sealing profile to be installed in accordance with smallradii without any creases. The production of this known tubular profilecan be effected in two stages for example, wherein firstly the innerprofile that has a relatively thicker wall thickness is produced duringextrusion and wherein the second profile is then applied onto the first,once again using an extruder.

A further tube-like sealing element that consists of two profilessurrounding each other and is intended for use in motor vehicles isknown from EP 0 822 052 A1, wherein the inner and outer profiles of thesealing element can equally consist of sponge rubber. The production ofsuch a sealing profile assembled from two profile parts can be effectedduring co-extrusion. Whilst the outer profile is intended to provide thesealing functions, the inner profile is used to improve carryingcapacity.

On the basis thereof, it is the object of the invention to create asealing profile of the type mentioned in the introduction with regard tosimple efficient production, sufficient restoration capability, anexcellent sealing capacity and such surface properties in the region ofthe outer surfaces which permit simple possibilities for applying acoating, such as an anti-friction lacquer, fiber coating or the like.This object is achieved for a sealing profile of the generic type bymeans of the features of the characterizing part of claim 1.

The tubular profile consists of two profiles that are disposed oneinside the other and can be connected to each other. The basic principleof the subject matter of the invention resides in the fact that the twotubular profiles are to be chosen with the proviso that they eachfulfill, in addition to a mere connecting capability, essentialproperties of the sealing profile such as, for example, sufficientrestoration capability on the one hand and surface properties in theregion of the outer surfaces on the other hand. Consequently,optimization of the two profiles in terms of construction and materialis additionally provided, based on the possibilities for efficientlyassembling the sealing profile and good adaptability to mechanical andthermal property requirements.

The sealing profile in accordance with the invention is to be seen as aproduct which can be further processed to the greatest possible extentsince its outer surface properties permit different possibilities forcoating and adhering with other materials.

In accordance with the invention, a tubular profile combination isproposed, wherein it is hereby assumed that the resilient restoringforce of the sealing profile is essentially applied by the inner tubularprofile, whereas the outer tubular profile essentially has a sealingfunction since this, owing to its soft nature, permits preciseadaptation to dimensional inaccuracies and inequalities in the region ofthe boundary surfaces defining the sealing gap. The pressing forcenecessary for maintaining the seal is applied by the elastic deformationof the inner tubular profile occurring during the sealing phase. Byvirtue of the fact that the inner tubular profile is produced fromsilicone and the outer tubular profile is produced from a sponge rubber,soft rubber or of another elastomer such as for example an EDPM or TPE,the above requirements can be fulfilled in every regard.

In accordance with the features of claim 2, this material combinationalso permits efficient production possibilities during co-extrusion thatis known per se.

The features of claims 3 and 4 relate to alternative possibilities ofcoating the outer surface of the outer tubular profile. In this regard,the coating can be fiber coating, application of a lacquer e.g. ananti-friction lacquer or also a film that has been applied in a hot meltcoating method.

In accordance with the features of claims 5 and 6, the sealing profilein accordance with the invention can selectively be in an annularstructure or as a wound product. In particular, in the case of the usedmaterial combination of the two tubular profiles, there is also thepossibility of a subsequent, end-side adhesion process, in order toproduce an annular structure.

It can be seen from the above embodiments that in the sealing profile inaccordance with the invention a product is produced that fulfills all ofthe mechanical and thermal boundary conditions, can be used to thegreatest possible flexible extent and can be used in particular in theautomotive industry.

The FIGURE in the drawing shows the cross-section of a sealing profile 1that serves to seal a gap between parts that can move relative to eachother, for example between the outer boundary of a motor vehicle doorand the inner boundary, facing said outer boundary, of the opening to beclosed by the door. The sealing profile 1 is characterized on one sideby a strip-like adhesive region 2 via which it can be connected to theouter boundary of the motor vehicle door or the inner boundary of saidopening. However, this adhesive technology as such is not the subjectmatter of the invention and will not be described in detail hereinafter.

The sealing profile 1 is formed in a tube-like manner and surrounds athrough-going, identically-formed hollow space 3. It is incidentallyconstructed from an outer tubular profile 4 and an inner tubular profile5, which tubular profiles are formed in different ways in terms ofmaterial and with regard to their functions in terms of the sealingprofile.

The inner tubular profile 5 consists of silicone in accordance with theinvention. It is dimensioned and arranged with the proviso that thesealing profile 1, that undergoes deformations in the direction of thearrow 6 in dependence upon the relative position of the boundariesdefining the gap to the sealed, is given a sufficient, resilientrestoration capability that is stabile over time. Consequently, itfulfills a substantial function when the necessary pressing force in theregion of the sealing surfaces is provided. This restoration capabilityis mainly provided by the inner tubular profile 5 and only anunsubstantial amount by the outer tubular profile 4.

In contrast thereto, the outer tubular profile 4 consists of a softrubber, e.g. EPDM, and owing to its mechanical properties is used forprecise adaptation to the boundaries of the gap to be sealed. It thusconsists of a relatively softly conditioned material in comparison withthe inner tubular profile 5. Furthermore, it is chosen in accordancewith the invention with regard to its surface properties and can becompletely or partly covered with an anti-friction lacquer or othersurface coatings e.g. a fiber coating. A substantial further property ofthe outer tubular profile 4 thus resides in its suitability for adhesionwith conventional coatings that are used in the outer region of suchsealing profiles, in particular the ability to use a stabile,heat-resistant and wear-resisting bond.

The boundaries of the gap to be sealed are not illustrated in thedrawings. A connection to the one boundary is always provided via theadhesive region 2 so that the other boundary is disposed opposite theregion 2 and is located for example at location 7. The boundaries can bemoved in the direction of the arrow 6 to effect a sealing effect or todiscontinue the sealing effect.

The two tubular profiles 4, 5 can advantageously be produced ascontinuous profiles during co-extrusion, wherein a connection betweenthe two profiles is possible by means of a cross-linking arrangement oralso by means of adhesive. The sealing profile 1 can thus be producedcontinuously in an in-line process and is characterized, in addition toa high, resilient adjustment capability, by heat-resistant and surfaceproperties that are specifically suited to the requirements of sealingprofiles used in the automotive industry.

1. Sealing profile (1) for sealing a gap between the outer boundary of aflat, movable first part and the inner boundary of an opening in afixedly disposed second part that can be closed by the first part, forexample for sealing the gap between a motor vehicle door and itsallocated opening of a motor vehicle construction, having a strip-likeadhesive region (2) that is intended to connect to one of theboundaries, having a tube-like construction surrounding a hollow space(3) and consisting of at least two tubular profiles that are disposedone inside the other and can be connected to each other, characterizedin that the two tubular profiles are created in different ways in termsof material, wherein the inner tubular profile (5) is chosen accordingto its resilient restoring force and wherein the outer tubular profile(4) is chosen according to its surface properties; in particular itsability to be coated and in comparison to the inner tubular profile (5)has a softer nature and a lower restoring force and wherein the innertubular profile (5) consists of silicone and the outer tubular profileconsists of a sponge rubber or a
 2. Sealing profile (1) according toclaim 1, characterized in that the two tubular profiles are profilesthat can be connected to the sealing profile during co-extrusion in anin-line process.
 3. Sealing profile according to claim 1, characterizedby a coating such as an anti-friction lacquer or fiber coating etc. thatis applied to the exterior of the outer tubular profile (4) and at leastpartly covers this outer surface.
 4. Sealing profile (1) according toclaim 1, characterized by a film that is connected to the exterior ofthe outer tubular profile (4), is applied in a hot melt coating methodand forms an outer coating.
 5. Sealing profile (1) according to claim 1,characterized by a construction as a wound profile.
 6. Sealing profileaccording to claim 1, characterized by a closed, annular construction.7. Sealing profile according to claim 2, characterized by a coating suchas an anti-friction lacquer or fiber coating etc. that is applied to theexterior of the outer tubular profile (4) and at least partly coversthis outer surface.
 8. Sealing profile (1) according to claim 2,characterized by a film that is connected to the exterior of the outertubular profile (4), is applied in a hot
 9. Sealing profile (1)according to claim 3, characterized by a film that is connected to theexterior of the outer tubular profile (4), is applied in a hot meltcoating method and forms an outer coating.
 10. Sealing profile (1)according to claim 2, characterized by a construction as a woundprofile.
 11. Sealing profile (1) according to claim 3, characterized bya construction as a wound profile.
 12. Sealing profile (1) according toclaim 4, characterized by a construction as a wound profile.
 13. Sealingprofile according to claim 2, characterized by a closed, annularconstruction.
 14. Sealing profile according to claim 3, characterized bya closed, annular construction.
 15. Sealing profile according to claim4, characterized by a closed, annular construction.